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SeaMonkey 2.53.18

  -  51.33 MB  -  Open Source
Free Download

Security Status

Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of SeaMonkey 2.53.18.


For those interested in downloading the most recent release of SeaMonkey for Mac or reading our review, simply click here.


All old versions distributed on our website are completely virus-free and available for download at no cost.


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Download SeaMonkey 2.53.18

  • SeaMonkey 2.53.18 Screenshots

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    SeaMonkey 2.53.18 Screenshot 1
  • SeaMonkey 2.53.18 Screenshot 2
  • SeaMonkey 2.53.18 Screenshot 3
  • SeaMonkey 2.53.18 Screenshot 4
  • SeaMonkey 2.53.18 Screenshot 5

What's new in this version:

- Update Branding info bug 1841167
- Use BugSplat for SeaMonkey crash reporting bug 1835524
- Unify notifications and permissions in SeaMonkeybug 1849526

The following bugs were fixed in our branch of the Gecko source code only:
- Update the NSS and NSPR libraries to the esr 115 versions for the final 2.53.18 release
- Allow building with system icu again in the final 2.53.18 releasebug 1864745

SeaMonkey 2.53.18 contains (among other changes) the following major changes relative to SeaMonkey 2.49.5:
- The Bookmarks Manager has switched its name to Library, and now also includes the History list. When History is invoked, the Library will be shown with the History list selected. The extensive modifications were needed because of Mozilla Gecko platform API changes.
- Download Manager has been migrated to a new API. Although it looks pretty much the same as before, the search option is missing and some other minor details work differently. The previous downloads history is removed during the upgrade.
- The layout panel was added to the CSS Grid tools.
- TLS 1.3 is the default SSL version now.
- Support for all NPAPI plugins like Flash, Java and Silverlight has been removed. For displaying pdf files in the browser you can use pdf.js-seamonkey from Isaac Schemm.
- SeaMonkey now uses a new api for formatting regional data like time and date. Default is to use the application locale of the current SeaMonkey build. If you use a language pack or a different OS formatting this is usually not desired. You can change the formatting from the application locale to the regional settings locale (OS) in the preferences dialog under "Appearance".

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